Romans 1:9 [AV]
For God is my witness, whom I serve with my spirit in the gospel of his Son, that without ceasing I make mention of you always in my prayers;

ANNOTATED NOTES:

God is my witness: only God and the individual knows what goes on within the secrecy of an individual's heart (1 Cor 2:11). So while enemies of Paul (and of Christ) were trying to defame and slander Paul and the gospel of God he preached, God has Paul boldly declare that HE is his witness (see Rom 9:1; Phil 1:8; I Thes 2:5; I Tim 2:7).

serve = latreuo: to perform sacred service; involves worshipful service (in 21 occurrences, it’s translated a form of “worship” 4x in the AV); an irreplaceable aspect of how Paul worshipfully served God was by praying for those who believed the gospel (see Luke 2:37)

spirit = pneuma: this usage of “spirit" refers to the entirety of his soul life; thus “with my spirit” here could accurately be understood as “with my whole heart and life”.

gospel of his Son: “gospel concerning his Son”, with the emphasis in this phrase on “Son”; it’s the good news from God concerning His Son

without ceasing: does not mean continuously, 24/7; it means daily, time and time again, he remembers to pray for them. In I Thes 5:17, we are exhorted to have the same consistency and faithfulness. See Eph 1:15-16; Phil 1:3-4; Col 1:3-4; I Thes 1:2-3 and I Thes 2:13 for Paul’s habit patterns in prayer.

ALTERNATIVE TRANSLATIONS:

Romans 1:9 [CEV]
God has seen how I never stop praying for you, while I serve him with all my heart and tell the good news about his Son.

Romans 1:9 [WUEST]
for my witness is God, to whom I render sacred service in my spirit in the good news concerning His Son, how unceasingly I am making mention of you always at my prayers,

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